//
//  CalendarUtil.swift
//  SimpleCal
//
//  Created by 杜晓祥 on 2021/10/19.
//

import Foundation

class CalendarUtil {
    
    private static let SOLAR_CALENDAR = Calendar.current
    private static let LUNAR_CALENDAR = Calendar.init(identifier: .chinese)
    
    private static let MONTH_DAY_NUMBER = [31,0,31,30,31,30,31,31,30,31,30,31]
    
    public static let CN_YEAR_MONTH = "yyyy年MM月"
    public static let DATE_FORMATTER = "yyyy-MM-dd"
    
    private static let LUNAR_DAY_STRING:[String:Int] = [
        "初一":1,"初二":2,"初三":3,"初四":4,"初五":5,"初六":6,"初七":7,"初八":8,"初九":9,"初十":10,
        "十一":11,"十二":12,"十三":13,"十四":14,"十五":15,"十六":16,"十七":17,"十八":18,"十九":19,"二十":20,
        "廿一":21,"廿二":22,"廿三":23,"廿四":24,"廿五":25,"廿六":26,"廿七":27,"廿八":28,"廿九":29,"三十":30,
        "二十一":21,"二十二":22,"二十三":23,"二十四":24,"二十五":25,"二十六":26,"二十七":27,"二十八":28,"二十九":29,"三十一":30,"卅一":31
    ]
    
    private static let LUNAR_MONTH_STRING = ["正":1,"一":1, "二":2, "三":3, "四":4, "五":5, "六":6, "七":7, "八":8, "九":9, "十":10, "十一":11, "冬":11, "十二":12, "腊":12]

    private static let LUNAR_MONTH_TO_STRING = ["正月", "二月", "三月", "四月", "五月", "六月", "七月", "八月", "九月", "十月", "冬月", "腊月"]

    static let LUNAR_DAY_TO_STRING = ["初一", "初二", "初三", "初四", "初五", "初六", "初七", "初八", "初九", "初十",
                            "十一", "十二", "十三", "十四", "十五", "十六", "十七", "十八", "十九", "二十",
                            "廿一", "廿二", "廿三", "廿四", "廿五", "廿六", "廿七", "廿八", "廿九", "三十"]
    
    private static let WEEK_STRING = ["日","一", "二", "三", "四", "五", "六"]
    
    static let LUNAR_TEST_DAY_TO_STRING = ["〇","一", "二", "三", "四", "五", "六", "七", "八", "九", "十",
                            "十一", "十二", "十三", "十四", "十五", "十六", "十七", "十八", "十九", "二十",
                            "廿一", "廿二", "廿三", "廿四", "廿五", "廿六", "廿七", "廿八", "廿九", "三十",
                            "卅一", "卅二", "卅三", "卅四", "卅五", "卅六", "卅七", "卅八", "卅九","四十",
                            "卌一", "卌二", "卌三", "卌四", "卌五", "卌六", "卌七", "卌八", "卌九", "五十"]
    
    private static let LUNAR_TIANGAN = ["甲","乙","丙","丁","戊","己","庚","辛","壬","癸"]
    private static let LUNAR_DIZHI = ["子","丑","寅","卯","辰","巳","午","未","申","酉","戌","亥"]
    private static let LUNAR_SHENGXIAO = ["鼠","牛","虎","兔","龙","蛇","马","羊","猴","鸡","狗","猪"]
    
    static func getFormatter (formatter:String, date:Date) -> String {
        let f = DateFormatter()
        f.dateFormat = formatter
        return f.string(from: date)
    }
    
    /**
     根据输入的年月日信息，生成Date对象
     */
    static func getDate(year:Int, month:Int, day:Int) -> Date {
        var components = DateComponents.init()
        components.year = year
        components.month = month
        components.day = day
        components.hour = 0
        components.minute = 0
        components.second = 0
        components.nanosecond = 0
        let newDate = SOLAR_CALENDAR.date(from: components)!
        return newDate
    }
    
    static func getCurrentYear() -> Int {
        return getCurrent(.year)
    }
    
    static func getCurrentMonth() -> Int {
        return getCurrent(.month)
    }
    
    static func getCurrentDay() -> Int {
        return getCurrent(.day)
    }
    
    static func getCurrent(_ component: Calendar.Component) -> Int {
        let d = Date()
        return SOLAR_CALENDAR.component(component, from: d)
    }
    
    /**
     根据日期对象，生成公历实体类信息
     */
    static func getSolarEntity(date:Date, solar: inout SolarEntity) {
        solar.year = SOLAR_CALENDAR.component(.year, from: date)
        solar.month = SOLAR_CALENDAR.component(.month, from: date)
        solar.day = SOLAR_CALENDAR.component(.day, from: date)
        solar.week = SOLAR_CALENDAR.component(.weekday, from: date)
        solar.weekOfMonth = SOLAR_CALENDAR.component(.weekOfMonth, from: date)
        solar.weekOfYear = SOLAR_CALENDAR.component(.weekOfYear, from: date)
        solar.hour = SOLAR_CALENDAR.component(.hour, from: date)
        solar.minute = SOLAR_CALENDAR.component(.minute, from: date)
        solar.second = SOLAR_CALENDAR.component(.second, from: date)
        solar.date = date
    }
    
    /**
     返回当前时间的公历实体类信息
     */
    static func getNowDate () -> SolarEntity {
        let d:Date = Date()
        var solar = SolarEntity()
        getSolarEntity(date: d, solar: &solar)
        return solar
    }
    
    static func getNowDateEntity () -> DateEntity {
        let solar = getNowDate()
        let lunar = solarToLunar(solar: solar)
        return DateEntity(lunar: lunar, solar: solar)
    }
    
    static func getDateEntity(year:Int, month:Int, day:Int) -> DateEntity {
        let solar = getSolarEntity(year: year, month: month, day: day)
        let lunar = solarToLunar(solar: solar)
        return DateEntity(lunar: lunar, solar: solar)
    }
    
    static func getDateEntity(year:Int, month:Int) -> DateEntity {
        return getDateEntity(year: year, month: month, day: 1)
    }
    
    /**
     指定日期的公历实体类对象信息
     */
    static func getSolarEntity (year:Int, month:Int, day:Int) -> SolarEntity {
        let d:Date = getDate(year: year, month: month, day: day)
        var solar = SolarEntity()
        getSolarEntity(date: d, solar: &solar)
        return solar
    }
    
    /**
     日期天数减一
     */
    static func dayDec (solar:SolarEntity) -> SolarEntity {
        return getSolarEntity(year: solar.year, month: solar.month, day: solar.day - 1)
    }
    
    /**
     日期天数加一
     */
    static func dayInc (solar:SolarEntity) -> SolarEntity {
        return getSolarEntity(year: solar.year, month: solar.month, day: solar.day + 1)
    }
    
    /**
     日期天数减一
     */
    static func dayDec (date: DateEntity) -> DateEntity {
        let solar = dayDec(solar: date.solar)//getSolarEntity(year: date.solar.year, month: date.solar.month, day: date.solar.day - 1)
        let lunar = solarToLunar(solar: solar)
        return DateEntity(lunar: lunar, solar: solar)
    }
    
    /**
     日期天数加一
     */
    static func dayInc (date: DateEntity) -> DateEntity {
        let solar = dayInc(solar: date.solar)//getSolarEntity(year: date.solar.year, month: date.solar.month, day: date.solar.day + 1)
        let lunar = solarToLunar(solar: solar)
        return DateEntity(lunar: lunar, solar: solar)
    }
    
    /**
     日期月份递减，每次调用月份减一
     */
    static func monthDec(solar:SolarEntity) -> SolarEntity {
        return getSolarEntity(year: solar.year, month: solar.month - 1, day: solar.day)
    }
    
    /**
     日期月份递增，每次调用月份加一
     */
    static func monthInc(solar:SolarEntity) -> SolarEntity {
        return getSolarEntity(year: solar.year, month: solar.month + 1, day: solar.day)
    }
    
    /**
     日期月份递减，每次调用月份减一
     */
    static func monthDec(date: DateEntity) -> DateEntity {
        let solar = monthDec(solar: date.solar)//getSolarEntity(year: solar.year, month: solar.month - 1, day: solar.day)
        let lunar = solarToLunar(solar: solar)
        return DateEntity(lunar: lunar, solar: solar)
    }
    
    /**
     日期月份递增，每次调用月份加一
     */
    static func monthInc(date:DateEntity) -> DateEntity {
        let solar = monthInc(solar: date.solar)//getSolarEntity(year: solar.year, month: solar.month + 1, day: solar.day)
        let lunar = solarToLunar(solar: solar)
        return DateEntity(lunar: lunar, solar: solar)
    }
    
    /**
     判断是否为当前月
     */
    static func isCurrentMonth (date: DateEntity) -> Bool {
        let now = getNowDateEntity()
        if date.equalMonth(date: now) {
            return true
        }
        return false
    }
    static func isToday (date: DateEntity) -> Bool {
        let now = getNowDateEntity()
        if date.equal(date: now) {
            return true
        }
        return false
    }
    
    static func isPreMonth (date:DateEntity) -> Bool {
        let now = getNowDateEntity()
        if now.preMonth(date: date) {
            return true
        }
        return false
    }
    
    static func isNextMonth (date:DateEntity) -> Bool {
        let now = getNowDateEntity()
        if now.nextMonth(date: date) {
            return true
        }
        return false
    }

    
    /**
     判断是否为闰年
     */
    static func isLeapYear(year:Int) -> Bool {
        return (year % 400 == 0) || ((year % 4 == 0) && (year % 100 != 0))
    }
    
    static func getMonthDays (year:Int, month:Int) -> Int {
        let m = MONTH_DAY_NUMBER[month - 1]
        if m != 0 {
            return m
        }
        return isLeapYear(year: year) ? 29 : 28
    }
    
    /**
     计算两个日期相差多少天
     */
    static func dateCalculate (solar1:SolarEntity, solar2:SolarEntity) -> Int {
        let date1 = getDate(year: solar1.year, month: solar1.month, day: solar1.day)
        let date2 = getDate(year: solar2.year, month: solar2.month, day: solar2.day)
        let dc = SOLAR_CALENDAR.dateComponents([.day], from: date1, to: date2)
        guard dc.day != nil else {
            return 0
        }
        return dc.day!
    }
    
    /**
     计算传入日期到今天相差多少天
     */
    static func dateCalculate (solar: SolarEntity) -> Int {
        return dateCalculate(solar1: getNowDate(), solar2: solar)
    }
    
    /**
     计算指定日期为当年度的第几天
     */
    static func whatDay (year:Int, month:Int, day:Int) -> Int {
        var days = 0
        var i = 0
        while i < month - 1 {
            days += getMonthDays(year: year, month: i + 1)
            i = i + 1
        }
        return days + day
    }
    
    /**
     计算指定日期为当年的第几天
     */
    static func whatDay(solar:SolarEntity) -> Int {
        return whatDay(year: solar.year, month: solar.month, day: solar.day)
    }
    
    /**
     计算指定年份有多少天
     */
    static func getYearDays(year:Int) -> Int {
        return isLeapYear(year: year) ? 366 : 365
    }
    
    /**
     计算指定日期和占全年的百分比
     */
    static func getPastTime (year:Int, month:Int, day:Int) -> Double {
        return (Double(whatDay(year: year, month: month, day: day)) / Double(getYearDays(year: year))) * 100
    }
    
    /**
     计算指定日期和占全年的百分比
     */
    static func getPastTime (solar:SolarEntity) -> Double {
        return getPastTime(year: solar.year, month: solar.month, day: solar.day)
    }
    
    static func getWeekStr(week:Int, pre:String) -> String {
        return pre + WEEK_STRING[week - 1]
    }
    
    static var milliStamp:Int64 {
        let timeInterval: TimeInterval = Date().timeIntervalSince1970
        return CLongLong(round(timeInterval * 1000))
    }
    
    //----------------------农历方法----------------------
    /**
     
     根据公历信息获取农历
     */
    static func solarToLunar (solar:SolarEntity) -> LunarEntity {
        var components = DateComponents()
        components.year = solar.year
        components.month = solar.month
        components.day = solar.day
        components.hour = 12
        components.minute = 0
        components.second = 0
        components.timeZone = TimeZone.init(secondsFromGMT: 60*60*8)
        let solarDate = SOLAR_CALENDAR.date(from: components)
        let formatter = DateFormatter()
        formatter.locale = Locale(identifier: "zh_CN")
        formatter.dateStyle = .long
        formatter.calendar = LUNAR_CALENDAR
        
        //let solar = LunarToSolar.convert(year: 2023, m:102, day: 5)
        //print("公历：\(solar.0)年\(solar.1)月\(solar.2)日")
        
        let lunarStr = formatter.string(from: solarDate!)
        let split0 = lunarStr.split(separator: "年")
        let y = split0[0].prefix(4)
        let sp1 = split0[1].split(separator: "月")
        let m = sp1[0]
        let d = sp1[1]
        var lunar = LunarEntity()
        lunar.year = Int(String(y))!
        lunar.month = getLunarMonth(month: String(m))
        lunar.day = getLunarDay(day: String(d))
        return lunar
    }
    
    private static func getLunarMonth(month:String) -> Int {
        if month.prefix(1) == "闰" {
            
            return (LUNAR_MONTH_STRING[String(month.suffix(1))] ?? -101) + 100
        }
        return LUNAR_MONTH_STRING[month] ?? -1
    }
    
    private static func getLunarDay (day:String) -> Int {
        
        return LUNAR_DAY_STRING[day] ?? -1
    }
    
    static func getLunarMonthStr(month:Int) -> String {
        if month > 100 {
            return "闰" + LUNAR_MONTH_TO_STRING[month - 101]
        }
        return LUNAR_MONTH_TO_STRING[month - 1]
    }
    
    static func getLunarDayStr(day:Int) -> String {
        return LUNAR_DAY_TO_STRING [day - 1]
    }
    
    static func getLunarTGYear(year:Int) -> String {
        var n = (year - 3) % 10
        n = n == 0 ? 10 : n
        return LUNAR_TIANGAN[n - 1]
    }
    static func getLunarDZYear(year:Int) -> String {
        var n = (year - 3) % 12
        n = n == 0 ? 12 : n
        return LUNAR_DIZHI[n - 1]
    }
    static func getLunarSXYear (year: Int) -> String {
        var n = (year - 3) % 12
        n = n == 0 ? 12 : n
        return LUNAR_SHENGXIAO[n - 1]
    }

    static func getLunarGZYear(year:Int) -> String {
        return "\(getLunarTGYear(year: year))\(getLunarDZYear(year: year))"
    }
    
    static func lunarToSolar(lunar:LunarEntity) -> SolarEntity {
        let n = LunarToSolar.convert(year: lunar.year, m: lunar.month, day: lunar.day)
        return getSolarEntity(year: n.0, month: n.1, day: n.2)
    }
    
    
    private class LunarToSolar {
        private static let lunar_month_days = [
                1887, 0x1694, 0x16aa, 0x4ad5, 0xab6, 0xc4b7, 0x4ae, 0xa56, 0xb52a, 0x1d2a,
                0xd54, 0x75aa, 0x156a, 0x1096d, 0x95c, 0x14ae, 0xaa4d, 0x1a4c, 0x1b2a,
                0x8d55, 0xad4, 0x135a, 0x495d, 0x95c, 0xd49b, 0x149a, 0x1a4a, 0xbaa5, 0x16a8,
                0x1ad4, 0x52da, 0x12b6, 0xe937, 0x92e, 0x1496, 0xb64b, 0xd4a, 0xda8, 0x95b5,
                0x56c, 0x12ae, 0x492f, 0x92e, 0xcc96, 0x1a94, 0x1d4a, 0xada9, 0xb5a, 0x56c,
                0x726e, 0x125c, 0xf92d, 0x192a, 0x1a94, 0xdb4a, 0x16aa, 0xad4, 0x955b,
                0x4ba, 0x125a, 0x592b, 0x152a, 0xf695, 0xd94, 0x16aa, 0xaab5, 0x9b4, 0x14b6,
                0x6a57, 0xa56, 0x1152a, 0x1d2a, 0xd54, 0xd5aa, 0x156a, 0x96c, 0x94ae, 0x14ae,
                0xa4c, 0x7d26, 0x1b2a, 0xeb55, 0xad4, 0x12da, 0xa95d, 0x95a, 0x149a, 0x9a4d,
                0x1a4a, 0x11aa5, 0x16a8, 0x16d4, 0xd2da, 0x12b6, 0x936, 0x9497, 0x1496,
                0x1564b, 0xd4a, 0xda8, 0xd5b4, 0x156c, 0x12ae, 0xa92f, 0x92e, 0xc96, 0x6d4a,
                0x1d4a, 0x10d65, 0xb58, 0x156c, 0xb26d, 0x125c, 0x192c, 0x9a95, 0x1a94,
                0x1b4a, 0x4b55, 0xad4, 0xf55b, 0x4ba, 0x125a, 0xb92b, 0x152a, 0x1694, 0x96aa,
                0x15aa, 0x12ab5, 0x974, 0x14b6, 0xca57, 0xa56, 0x1526, 0x8e95, 0xd54, 0x15aa,
                0x49b5, 0x96c, 0xd4ae, 0x149c, 0x1a4c, 0xbd26, 0x1aa6, 0xb54, 0x6d6a, 0x12da,
                0x1695d,0x95a, 0x149a, 0xda4b, 0x1a4a, 0x1aa4, 0xbb54, 0x16b4, 0xada, 0x495b,
                0x936, 0xf497, 0x1496, 0x154a, 0xb6a5, 0xda4, 0x15b4, 0x6ab6, 0x126e, 0x1092f,
                0x92e, 0xc96, 0xcd4a, 0x1d4a, 0xd64, 0x956c, 0x155c, 0x125c, 0x792e, 0x192c,
                0xfa95, 0x1a94, 0x1b4a, 0xab55, 0xad4, 0x14da, 0x8a5d, 0xa5a, 0x1152b, 0x152a,
                0x1694, 0xd6aa, 0x15aa, 0xab4, 0x94ba, 0x14b6, 0xa56, 0x7527, 0xd26, 0xee53,
                0xd54, 0x15aa, 0xa9b5, 0x96c, 0x14ae, 0x8a4e, 0x1a4c, 0x11d26, 0x1aa4, 0x1b54,
                0xcd6a, 0xada, 0x95c, 0x949d, 0x149a, 0x1a2a, 0x5b25, 0x1aa4, 0xfb52, 0x16b4,
                0xaba, 0xa95b, 0x936, 0x1496, 0x9a4b, 0x154a, 0x136a5, 0xda4, 0x15ac ]
        
        private static let solar_1_1 = [
            1887, 0xec04c, 0xec23f, 0xec435, 0xec649, 0xec83e, 0xeca51, 0xecc46, 0xece3a,
            0xed04d, 0xed242, 0xed436, 0xed64a, 0xed83f, 0xeda53, 0xedc48, 0xede3d,
            0xee050, 0xee244, 0xee439, 0xee64d, 0xee842, 0xeea36, 0xeec4a, 0xeee3e,
            0xef052, 0xef246, 0xef43a, 0xef64e, 0xef843, 0xefa37, 0xefc4b, 0xefe41,
            0xf0054, 0xf0248, 0xf043c, 0xf0650, 0xf0845, 0xf0a38, 0xf0c4d, 0xf0e42,
            0xf1037, 0xf124a, 0xf143e, 0xf1651, 0xf1846, 0xf1a3a, 0xf1c4e, 0xf1e44,
            0xf2038, 0xf224b, 0xf243f, 0xf2653, 0xf2848, 0xf2a3b, 0xf2c4f, 0xf2e45,
            0xf3039, 0xf324d, 0xf3442, 0xf3636, 0xf384a, 0xf3a3d, 0xf3c51, 0xf3e46,
            0xf403b, 0xf424e, 0xf4443, 0xf4638, 0xf484c, 0xf4a3f, 0xf4c52, 0xf4e48,
            0xf503c, 0xf524f, 0xf5445, 0xf5639, 0xf584d, 0xf5a42, 0xf5c35, 0xf5e49,
            0xf603e, 0xf6251, 0xf6446, 0xf663b, 0xf684f, 0xf6a43, 0xf6c37, 0xf6e4b,
            0xf703f, 0xf7252, 0xf7447, 0xf763c, 0xf7850, 0xf7a45, 0xf7c39, 0xf7e4d,
            0xf8042, 0xf8254, 0xf8449, 0xf863d, 0xf8851, 0xf8a46, 0xf8c3b, 0xf8e4f,
            0xf9044, 0xf9237, 0xf944a, 0xf963f, 0xf9853, 0xf9a47, 0xf9c3c, 0xf9e50,
            0xfa045, 0xfa238, 0xfa44c, 0xfa641, 0xfa836, 0xfaa49, 0xfac3d, 0xfae52,
            0xfb047, 0xfb23a, 0xfb44e, 0xfb643, 0xfb837, 0xfba4a, 0xfbc3f, 0xfbe53,
            0xfc048, 0xfc23c, 0xfc450, 0xfc645, 0xfc839, 0xfca4c, 0xfcc41, 0xfce36,
            0xfd04a, 0xfd23d, 0xfd451, 0xfd646, 0xfd83a, 0xfda4d, 0xfdc43, 0xfde37,
            0xfe04b, 0xfe23f, 0xfe453, 0xfe648, 0xfe83c, 0xfea4f, 0xfec44, 0xfee38,
            0xff04c, 0xff241, 0xff436, 0xff64a, 0xff83e, 0xffa51, 0xffc46, 0xffe3a,
            0x10004e, 0x100242, 0x100437, 0x10064b, 0x100841, 0x100a53, 0x100c48,
            0x100e3c, 0x10104f, 0x101244, 0x101438, 0x10164c, 0x101842, 0x101a35,
            0x101c49, 0x101e3d, 0x102051, 0x102245, 0x10243a, 0x10264e, 0x102843,
            0x102a37, 0x102c4b, 0x102e3f, 0x103053, 0x103247, 0x10343b, 0x10364f,
            0x103845, 0x103a38, 0x103c4c, 0x103e42, 0x104036, 0x104249, 0x10443d,
            0x104651, 0x104846, 0x104a3a, 0x104c4e, 0x104e43, 0x105038, 0x10524a,
            0x10543e, 0x105652, 0x105847, 0x105a3b, 0x105c4f, 0x105e45, 0x106039,
            0x10624c, 0x106441, 0x106635, 0x106849, 0x106a3d, 0x106c51, 0x106e47,
            0x10703c, 0x10724f, 0x107444, 0x107638, 0x10784c, 0x107a3f, 0x107c53,
            0x107e48 ]
        
        private static func GetBitInt(data:Int, length:Int, shift:Int) -> Int {
                return (data&(((1<<length)-1)<<shift))>>shift
                 
            }
        
        private static func SolarToInt(year:Int, month:Int, day:Int) -> Int {
                let m = (month + 9) % 12
                let y = year - m / 10
                 
                return 365 * y + y / 4 - y / 100 + y / 400 + (m * 306 + 5) / 10 + (day - 1)
            }
        
        private static func SolarFromInt(g:Int) -> (Int, Int, Int){
                var y = (10000*g+14780)/3652425
                var ddd = g-(365*y+y/4-y/100+y/400)
                if ddd < 0 {
                    y=y-1
                    ddd = g-(365*y+y/4-y/100+y/400)
                }
                let mi = (100*ddd+52)/3060
                let mm = (mi+2)%12+1
                y = y+(mi+2)/12
                let dd = ddd-(mi*306+5)/10+1
                //return "\(y) \(mm) \(dd)"
                return (y, mm, dd)
            }
        
        fileprivate static func convert(year: Int, m: Int, day: Int) -> (Int, Int, Int){
                var month = m
                let days = lunar_month_days[year-lunar_month_days[0]]
                let leap = GetBitInt(data: days, length: 4, shift: 13)
                var offset = 0
                var loopend = leap
                //判断是否是闰月
                var isleap = false
                if month > 100 {
                    month = month - 100
                    isleap = true
                } else {
                    isleap = false
                     
                }

                if !isleap {
                    if month <= leap || leap == 0 {
                        loopend = month-1
                    } else {
                        loopend = month
                         
                    }
                }
                for i in 0..<loopend {
                    offset += GetBitInt(data: days, length: 1, shift: 12-i) == 1 ? 30 : 29
                }
                offset += day
                let solar11 = solar_1_1[year-solar_1_1[0]]
                let y = GetBitInt(data: solar11, length: 12, shift: 9)
                let m = GetBitInt(data: solar11, length: 4, shift: 5)
                let d = GetBitInt(data: solar11, length: 5, shift: 0)
                let g = SolarToInt(year: y, month: m, day: d)+offset-1
                return SolarFromInt(g: g)
            }
    }
}
